His Royal Highness Prince Kyril of Bulgaria (17 November 1895 - 1 February 1945) was the brother of Tsar Boris III of Bulgaria.

After the death of Boris on August 28 1943, Kyril was appointed head of a regency council by the Bulgarian parliament, to act as Head of State until the late Tsar's son, Simeon II became 18.

In 1945 a Soviet-backed military coup assumed power in Bulgaria, which instituted war crimes trials against the regency council. Prince Kyril was found guilty of collaboration with Germany and was sentenced to death. According to some accounts, he was made to dig his own grave before being shot through the back of the head.